Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted to be prior art by inclusion in this section.
High-efficiency video coding (HEVC) is a new-generation video coding standard developed by the Joint Collaborative Team on Video Coding (JCT-VC). FIG. 9 provides the block diagram of the HEVC encoding system. When the current coding unit is predicted in the Inter mode, the pixels in a prediction unit are predicted by the reconstructed pixels in the coded reference frame after motion compensation, followed by residual coding. The motion information is represented by signaling the motion vector difference (MVD) between a motion vector and a predicted motion vector in the bitstream.
The JCT standardization body is currently in the process of developing the screen content coding (SCC) extension. A new intra block copy (IntraBC) tool, indicated by a new syntax flag intra_bc_flag, has been adopted into the HEVC SCC extension, as specified by HEVC Screen Content Coding: Draft 2 (JCTVC-S1005). When intra_bc_flag is equal to 1, the current coding unit (CU) is coded in the IntraBC mode and is predicted by the reconstructed block region of the same size before deblock and sample adaptive offset (SAO) filtering from the current frame, followed by residual coding. The location of the reference block is indicated by a block vector, specifying the coordinate offsets in the horizontal and vertical directions, respectively, from the current block. The block vector information is represented by signaling the block vector difference (BVD) between a block vector and a predicted block vector in the bitstream.